The anonymous, racially offensive Web posting that inspired a rally against racism at Trinity College last month was written by a black student who wanted to see how her schoolmates would respond.

"When I began writing the post, I imagined an argument whose effect would serve as a litmus test of the campus climate," the student, Lynda Ikejimba, wrote in a campuswide e-mail, apologizing for the post.

Ikejimba wrote in her apology that race relations "have not been optimal" on campus and that she wanted to find out how students felt about recent efforts to improve the culture at Trinity. She thought using the anonymous online forum TrinTalk would elicit honest answers and hoped that students would respond in disgust.

She called the post "the product of an egregious lapse in judgment" and said she did not intend that the comments leave the Web forum.

The comments disparaged minority students and said their admission to the college correlated with a drop in the college's rankings.